ask for help: How to make pcie-dpc detect DPC feature in platform device?

ask for help: How to make pcie-dpc detect DPC feature in platform device?

[Wang Sheng-Hui]

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Re: ask for help: How to make pcie-dpc detect DPC feature in platform device?

[Keith Busch]

On Mon, Oct 17, 2016 at 05:30:00PM -0700, Wang Sheng-Hui wrote:
> Keith,
> 
> Sorry to trouble you.
> 
> I'm making up a driver (DPC supported in the device) for our private SoC system, 
> and the driver is regarded as a platform driver.
> 
> I wonder how can I make the pcie-dpc driver detect my DPC-enabled SOC and tigger
> some action in my platform driver?
> 
> And one more question:
>            How to simulate DPC event in simulation env, e.g QEMU?

Sorry for the late reply. A lot of mailing list messages have been
redirected to my spam folder for some reason.

The pcie-dpc driver, if enabled in your kernel config, automatically
binds to any pcie downstream or root port that has the DPC capability. If
your DPC capable device is not seen as a root or downstream pcie port,
then pcie-dpc won't bind to it.

I don't see why you couldn't emulate the capability in QEMU, but I don't
see it implemented in any of the emulated pcie devices, so you'd have
to get someone to implement it in one of them.